Contacting liquids with gases or vapors



Oct. 28, 1952 DIXON CONTACTING LIQUIDS WITH GASES OR VAPORS Filed Feb25, 1947 INVENTOR. yeQz'xon mommy Patented Oct. 28, 1952 CONTACTINGmemos. wrrn erases on;

vArons Olaf George Dixon, Norton-on-Tees, England; as-

Signor to" Imperial Chemical Industries Limited', a corporation of GreatBritain Application February 25, 1941, Seria1No. 73.0,678.

In Great Britain February 28,. 1946 This invention relates to contactingliquids with gases in. such operations as performed in absorption,washing, and reaction towers, and condensers such as i'ractionatingcolumns or the like.

It has as its general object; the formation of a new typeof packing madeof galloon netting which has a high efficiency forthe purposes as usedin the examples above and yet does not require the heretofore necessarypreliminary flooding or prefl'ooding oi thetower or condenser and thesubsequent carefully controlled operating conditions in order toinitially thoroughly wet the packing with liquid. to ensure continuedintimate contact of the liquid and", vapor phases during such;operations;v i.

. In the drawings forming apart. of the specification, examples oftheuse of the packing and various modifications of the shapes of thepacking made of galloon netting are shown in which,

Figure 1 is a reduced scale side elevational view of a distillationdevice" having aside wall thereof broken away to show one manner ofdisposing therein packing material'such as shown in approximately fullscale in Figures 35' and 7-11, inclusive, made in accordance with thepresent invention.

Figure 2 is azfragmentary view: of an apparatus similar to Figure 1showing a. general arrangement of the new packing material arrangedsimilar to that set forth in. my copending application Seriai No.708.223;

Figure 3* is a side elevational view of a sheet of galloon netting,rectangular in shape, showingsubsta-ntially-the full size of one formthereof.

Figure 4 is a perspective view of a Raschig ring made of galloonnetting, being hollow in nature.

Figure 5 is a perspective view of a Lessing ring made of galloon nettingbeing hollow in nature.

Figure 6 is a perspective view of a section wound roll of galloonnetting which is suitable for use as a packing unit and would completelyfill the packing space of Figure 1, both Figure 1 and Figure 6 beingreduced in size while Figures 3-5 and 7-11 are approximately full scale.

Figure '7 is a perspective view of a section of fiat strip of galloonnetting twisted about its longitudinal axis to provide a hollowpropeller shaped filling unit for the vessel disclosed in Figure 2.

Figure 8 is a perspective view of a form of filler unit similar in shapeto a Berl ring.

Figure 9 is a perspective view of a hollow cylindrical filler made inaccordance with the pres- 4': Claims. (01. zenx01) ent invention'havinggaps in its walls.

Figure 10 is a perspective viewof a hollow filler, cylindrical in natureand having a longi'-' tudinalgapextendingover its entire length, thegalloonwa-rp thread running circumzferentially about the unit, and

Figure 11 is a perspective view of a wound roll filler having the warpthread" running in a circumferential direction about its axis and wouldbe one, of the many units randomly packed in the packing space of FigureI. I g

In this specification galloon netting refers, in vparticular, to wovenmaterial in which the warp threads are substantially straight instead ofbeing bent as in the case oi normal weaving while the weft threads arearranged closely against one another: The number of weft threads in (agalloon netting is, therefore, always greater than the number of warpthreads. Moreover, the warp thre'adsare generally, but not necessarily,thicker and/or stronger than the weft threads.

Twilledgalloon netting may be used 'but it is preferred to use galloonnetting of normal weave. The-galloon netting made be made from one ormore materials having suflicient mechanical strength, such as. wire,glass wool, slag wool, or filaments of synthetic resins. For example,the netting maybe made with. warp threads of wire andweft threads ofsynthetic resin. Ithas been found. convenient, however, to use galloonnetting made from wires: of suitable metals, such as copper, brass,Phosphor bronze, cupro-nickcl andstainlesssteel. 3

In Figure 1 is; shown a column or vessel gen.- erally indicated as lwith the side wall 2 thereof broken away to show the packing material 3thereof, which is shown in Figures 4-11, inclusive, arranged in anorderly manner in this example throughout the column. It is, of course,to be understood that the packing may be randomly packed if it is sodesired.

In Figure 2 aplurality of galloon sheets 4 are arranged vertically in arectangular tower or vessel 5 whose walls 6 are broken away to show thisarrangement.

In Figure 3is shown a sheet of galloon netting having warp threads 8 andweft threads 9.

The galloon netting may be made up into filling bodies of any suitableshapes as shown in Figures 3-11, inclusive. in these figures are wellknown as packing bodies and those that are not known areself-explanatory insofar as their particular shape is longitudinalopenings or Most of the shapes as set forth 1 ating conditions in orderto ensure intimate contact of the liquid which forms a film on thenetting and the vapor phase in the column during operation.

It should be understood that the mesh of the galloon netting and thethickness of the individual threads may be varied within wide limits butit has been found convenient when using netting made from wire, to haveseven warp wires per inch and forty-four weft wires per inch, thediameters of the wires being0.036 inch for the warp and 0.022 inch forthe weft. I

Where the galloon netting is to be made up into filling bodies in theform ofthe so-called Raschig rings, Lessing rings, and the like it hasbeen found convenient for the bodies to have adiameter not less than oneinch and a length equal to the diameter. I v

The pronounced self-wetting properties of galloon netting depend onlyslightly on the direction of the warp threads relative to the flow ofthe liquid, it being best when the warp threads are parallel to theflow; that is, for sheets in a column it is preferable for the warpthreads to be vertical. "In a sheet, this direction is also preferableon account of the warp threads greater thickness and/or strength.

With regards to filling bodies made from galloon netting it is concededthat if such bodies of cylindrical form are stacked in a regular patternlayerbylayer it is reasonable to suppose from the above remarks that inthis case also the warp wires should be vertically disposed. It has beenfound preferable, however, for the rigidity of the fillinbodies,particularly when these are randomly packed, to have the warpthreads circumferentially disposed in cylindrically shaped bodies andlongitudinally in the propeller and saddle shapes.

The packing of the present invention is suitable for use in a variety ofprocesses where it is desirable to present a large surface area ofliquid to gas or vapor, for example, in gas washing processes andparticularly in distillation.

In the appended claims the term gas, when used, designates bothsubstances which are gaseous under normal conditions of temperature andpressure, and normally liquid substances in vaporized form.

I claim:

1. Apparatus for contacting liquids with gases comprising a vesselcontaining a packing of vertically disposed plain sheets of galloonnetting, said sheets being spaced apart to provide between them at leastone free and unobstructed path for the upward flow of vapor, and meansfor supplyin liquid to the upper edges of the sheets, the weave of saidgalloon netting being sufficiently close to insure filming of the liquidacross the apertures therein.

2. Apparatus for contacting liquids with gases as set forth in claim 1wherein said vertically disposed sheets of galloon netting aresubstantially parallel.

3. Apparatus for the distillation of liquids which comprise a columncontaining a packing of verticallydisposed plain sheets of galloonnetting, said sheets being spaced apart to provide between them at leastone free'and unobstructed path for the upward flow of vapor, and meansfor supplying reflux liquid to the upper edges of the sheets, the weaveof said galloon nettin being sufliciently close to insure filming ofsaid reflux liquid across the apertures therein.

4. Apparatus for the distillation of liquids as set forth in claim 3wherein said vertically disposed sheets of galloon netting aresubstantially parallel.

OLAF GEORGE DIXON.

. REFERENCES CITED- The following references are of record in the fileof this patent:

v UNITED STATES PATENTS- Number Germany Aug. 29, 1912

